What is the temp coming out of the vents? Also, you do need a set of inexpensive gauges to proceed, and the first step would be to check static pressures on a cold engine, which means nothing running.
For example, if the engine and car are at 90F, the static high and low side pressure is probably around 100psi.
My guess is that you're just low on R134.
For example, if the engine and car are at 90F, the static high and low side pressure is probably around 100psi.
My guess is that you're just low on R134.